Learning VHDL - Basics
Since FPGA are becoming more accessible to the hobbyist, learning how to use them can be really useful for certain applications, like DSP and video generation; moreover, engineers that are able to code in VHDL/Verilog are always requested on the job market.
In this tutorial I will cover the basics of Xilinx ISE and VHDL. I willl base my code on the Basys2 board from Digilent: it is really cheap (especially for students) and has a lot of features on board, as you can see from the picture...
PicoBlaze - Program RAM Access for an Interactive Monitor
I have a confession to make: I love PicoBlaze! There are many reasons to love it. It is a tiny CPU (96 Spartan3 slices or 26 Spartan6 slices plus a BRAM). It is simple. It is bug-free. It's pretty fast. It can reduce the size and the complexity of your design - instead of debugging a big state machine, just throw one (or more) of these in. Add a serial output and you can debug your fpga from inside out!However, there are a few problems. The...
MyHDL ... MyPWM
The PWM topic appears to be popular lately on the fpgarelated site. This is coincidence, but I typically find the topic of modulating and demodulating signals interesting. For digital systems it is always entertaining to play with PWMs. The following PWM RTL description is quite a bit different than the PWM module described by Anton Babushkin. The module presented here is a minimal PWM engine defined at design time (i.e. not run-time).
As...
StrangeCPU #4. Microcode
Summary:Sliding windows containing runs of microcode.
Table of Contents:-
Part 1: A new CPU - technology review, re-examination of the premises; StrangeCPU concepts; x86 notes.
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Part 2: Sliding-Window Token Machines, an in-depth exploration of this curious technology; ARM notes.
StrangeCPU #3. Instruction Slides - The Strangest CPU Yet!
Summary:Decoding instructions with a Sliding Window system. 0-Bit Sliding Register Windows.
Table of Contents:- Part 1: A new CPU - technology review, re-examination of the premises; StrangeCPU concepts; x86 notes.
- Part 2: Sliding-Window Token Machines, an in-depth exploration of this curious technology; ARM notes.
- Part 3. Instruction Slides - The Strangest CPU Yet! Decoding instructions with a Sliding...
StrangeCPU #2. Sliding Window Token Machines
Summary:An in-depth exploration of Sliding Window Token Machines; ARM notes.
Table of Contents:- Part 1: A new CPU - technology review, re-examination of the premises; StrangeCPU concepts; x86 notes.
- Part 2: Sliding-Window Token Machines, an in-depth exploration of this curious technology; ARM notes.
- Part 3. Instruction Slides - The Strangest CPU Yet! Decoding instructions with a Sliding Window...
StrangeCPU #1. A new CPU
Summary: In this multi-part series I will share with you a design, implementation notes and code for a slightly different kind of a CPU featuring a novel token machine that resolves an 8-bit token to pretty much any address in a 32-bit or even 64-bit address space, using not much more than an adder.
Table of Contents:- Part 1: A new CPU - technology review, re-examination of the premises; StrangeCPU concepts; x86 notes.
MyHDL Resources and Projects
Last updated 07-Nov-2017
MyHDL ResourcesIf you want to dive into MyHDL (digital hardware description in Python) there are many resources available. Below is a list of MyHDL resources, including some of the past blogs here on fpgarelated.
The MyHDL manual is a great (probably the best) place to get started.
The manual is an in-depth introduction to MyHDL. The concepts are well explained and there are examples to test while working through the...
Two jobs
For those of you following closely embeddedrelated and the other related sites, you might have noticed that I have been less active for the last couple of months, and I will use this blog post to explain why. The main reason is that I got myself involved into a project that ended up using a better part of my cpu than I originally thought it would.
edit - video of the event:
I currently have two jobs: one as an electrical/dsp engineer recycled as a web publisher and the other...
Designing a FPGA Micro Pt1 - Start The Clock
Last time I talked about state machines and micro’s inside FPGAs and why you may want to consider having a micro. So lets say you have decided you want or need a micro in your FPGA design. Where will you start? Well there are lots to pick from but one option is to design your own. So with that in mind I decided to set myself the challenge of doing just that.
MyHDL FPGA Tutorial II cont. (Echo, Audio Interface)
IntroductionTo demonstrate the echo on an FPGA board an interface to an audio ADC/DAC chip will be used. The following will explain the connection to the audio codec and the HDL module used to interface.
Audio Codec InterfaceI have two boards with TI AIC23b audio codecs. The AIC23 has a configuration interface (ability to program the registers) and a streaming audio interface. The SPI mode will be used to configure the codec and the I2S interface is used to send and...
Designing a FPGA Micro Pt2 - Clock and Counter build and test.
So last time I looked and talked about designing my own PIC12F509. I concluded by talking shortly about the clock that is used inside the chip. If you have not read this it may be a good time to jump back and read what I have written so far. I’ll be putting links back at the top of every blog from now on to help.State Machine ‘v’ Micro in a FPGADesigning a FPGA Micro Pt1 - Start The ClockOk so this last week I started writing the VHDL code for my PIC core that I’ll be...
Use a Simple Microprogram Controller (MPC) to Speed Development of Complex Microprogrammed State Machines
IntroductionThis article will describe a synthesizable HDL-based microprogram controller (MPC), or microprogram sequencer (MPS), that can be used to provide the control of a microprogrammed state machine. Unlike the microprogrammed state machines that I described in my previous two articles, "Use Microprogramming to Save Resources and Add Functionality" and "Fit Sixteen (or more) Asynchronous Serial Receivers in the Area of a Standard UART", many microprogrammed state machines will...
StrangeCPU #3. Instruction Slides - The Strangest CPU Yet!
Summary:Decoding instructions with a Sliding Window system. 0-Bit Sliding Register Windows.
Table of Contents:- Part 1: A new CPU - technology review, re-examination of the premises; StrangeCPU concepts; x86 notes.
- Part 2: Sliding-Window Token Machines, an in-depth exploration of this curious technology; ARM notes.
- Part 3. Instruction Slides - The Strangest CPU Yet! Decoding instructions with a Sliding...
MyHDL synthesis: from browser to FPGA in five seconds
When it comes to feeding (mostly proprietary) synthesis tools, the most widely supported HDL (hardware design language) is probably plain Verilog, then comes VHDL. The reasons for that are simply based on popularity or the fact that VHDL is a little more complex to parse.
So, all super-HDLs (like Chisel, SpinalHDL, etc.) transfer to one of these V* HDLs in one way or another, then synthesis/mapping/place'n'route turns it into a wiring map for the silicon. Same went for MyHDL or its also...
Little to no benefit from C based HLS
Last updated 07-Nov-2015
As I write this I am on a plane and my destination is EELive 2014 where I am going to give a talk hardware design: the grunge era. It is a shotgun introduction to three alternative hardware description languages (alt.hdl). The three languages briefly introduced in the talk are: bsv, chisel, and myhdl. The goal of the talk is simply to raise awareness of the three...
MyHDL Resources and Projects
Last updated 07-Nov-2017
MyHDL ResourcesIf you want to dive into MyHDL (digital hardware description in Python) there are many resources available. Below is a list of MyHDL resources, including some of the past blogs here on fpgarelated.
The MyHDL manual is a great (probably the best) place to get started.
The manual is an in-depth introduction to MyHDL. The concepts are well explained and there are examples to test while working through the...
MyHDL ... MyPWM
The PWM topic appears to be popular lately on the fpgarelated site. This is coincidence, but I typically find the topic of modulating and demodulating signals interesting. For digital systems it is always entertaining to play with PWMs. The following PWM RTL description is quite a bit different than the PWM module described by Anton Babushkin. The module presented here is a minimal PWM engine defined at design time (i.e. not run-time).
As...
USB-FPGA : Introduction
This blog is an introduction to a series of blogs I hope to write. The blogs will cover the design and experiences I had on a project that spanned the last 6 years. The project was the development of an USB FPGA board and the supporting gateware, firmware, and software. The project has had different levels of activity over the years, ranging from none to some, but it has been an ongoing project, albeit, during sleepless nights. Lately, I have ported the HDL (gateware)...
Windows XP and Win32 - the Platform of the Future!
Over the past decade I often wondered why anyone uses Windows. It's just so... proprietary. And pedestrian. As I grew up my OS of choice went nothing to CPM to DOS (on Apple ][), GEM on Atari ST, MS-DOS, DOS extenders, Mac OS, Windows NT, Windows XP, Linux... Now, I again find myself a fan of Windows XP, the platform of the future. (I am still a fan of bare metal, of course).Maybe I am not totally serious, but I, a self-proclaimed freedom lover and...
Feedback Controllers - Making Hardware with Firmware. Part 5. Some FPGA Aspects.
This part of the on-going series of articles looks at a variety of aspects concerning the FPGA device which provides the high-speed maths capability for the low-latency controller and the arbitrary circuit generator application. In due course a complete specification along with application examples will be maintained on the project website here.- Part 5: Some FPGA Aspects (this part)
- Part 4: Engineering of...
Jumping from MCUs to FPGAs - 5 things you need to know
Are you a microcontroller expert beckoned by the siren song of the FPGA? Not long ago, that was me. FPGA-expert friends of mine regularly extolled the virtues of these mysterious components and I wanted in. When I made the leap, I found a world seemingly very familiar, but in reality, vastly different. I found that my years of C programming and microcontroller use often gave pre preconceived interpretations of FPGA resource material which resulted in eye-roll class mistakes in my code. I’ve gleaned five things of vital importance to help you make that transition faster than I did.
Project introduction: Digital Filter Blocks in MyHDL and their integration in pyFDA
Hi everyone! After a lot of hesitation and several failed attempts, I have finally entered the world of blogging. A little about myself : My name is Sriyash Caculo and I’m a third year undergrad student at BITS Pilani K.K. Birla Goa Campus pursuing a major in Electronics and Instrumentation engineering. Being an electronics engineer, I developed an interest in Digital Signal Processing and its implementation on hardware.
This blog-post is the first of many to come for the...
New book on Elliptic Curve Cryptography
New book on Elliptic Curve Cryptography now online. Deep discount for early purchase. Will really appreciate comments on how to improve the book because physical printing won't happen for a few more months. Check it out here: http://mng.bz/D9NA
binary hello world
Python + Ohio + MyHDL + FPGARecently I had the opportunity to coordinate a hands-on programmable hardware (FPGA) workshop (open-space) at a regional Python conference - @pyohio. The workshop was for those that had little to no exposure to programmable hardware. For this situation I used two basic examples: two versions of a binary hello world.
The binary hello world -- blinking an LED -- is a good starting point to introduce programmable hardware, hardware descriptions languages,...
Feedback Controllers - Making Hardware with Firmware. Part 8. Control Loop Test-bed
This part in the series will consider the signals, measurements, analyses and configurations for testing high-speed low-latency feedback loops and their controllers. Along with basic test signals, a versatile IFFT signal generation scheme will be discussed and implemented. A simple controller under test will be constructed to demonstrate the analysis principles in preparation for the design and evaluation of specific controllers and closed-loop applications.
Additional design...One Clock Cycle Polynomial Math
Error correction codes and cryptographic computations are most easily performed working with GF(2^n)
MyHDL synthesis: from browser to FPGA in five seconds
When it comes to feeding (mostly proprietary) synthesis tools, the most widely supported HDL (hardware design language) is probably plain Verilog, then comes VHDL. The reasons for that are simply based on popularity or the fact that VHDL is a little more complex to parse.
So, all super-HDLs (like Chisel, SpinalHDL, etc.) transfer to one of these V* HDLs in one way or another, then synthesis/mapping/place'n'route turns it into a wiring map for the silicon. Same went for MyHDL or its also...
FPGA skills for the modern world
With the ever increasing number of applications involving video processing, AI or edge computing the appetite for suitably skilled FPGA Engineers has never been higher from the market which is expected to grow to $15 billion USD by 2027!
In terms of industries opportunities can be typically found within:
- Automotive
- Aerospace
- Defense
- Data Processing
However this list is certainly not exhaustive as any application requiring algorithms which can leverage from highly parallel and...



















